Yarn winding mechanism



March 19, 1968 i, H, swAL' w 3,373,949

YARN WINDING MECHANISM Filed Oct. 4, 1965 2 Sheets-Sheet 1 o a 2 9 \f 1 L9 1 0 l /0 5 1 6 J o 2/ JW M //VVE7VTOR March 19; 1968 l. H. SWALLOW 3,373,949.

YARN WINDING MECHANISM Filed Oct. 4, 1965 2 Sheets-Shet z United States Patent Office 3,373,94 9 Patented Mar. 19, 1968 3,373,949 YARN WINDING MECHANISM Ian Henry Swallow, Goytre, Monmoutlishire, England, assignor to British Nylon Spinners Limited, Pontypool, Monmouthshire, England, a corporation of Great Britain Filed Oct. 4, 1965, Ser. No. 492,653 Claims priority, application Great Britain, Oct. 21, 1964, 42,939/64 8 Claims. (Cl. 242--43) ABSTRACT OF THE DISCLOSURE A yarn traversing mechanism for a rotating yarn package includes means for lubricating the sliding surfaces in the mechanism and means for preventing contamination of the yarn with lubricant. The mechanism includes a horizontally disposed, grooved barrel cam, a cam follower, parallel upper and lower guide tracks for the follower, a yarn guide carried by the follower and disposed on the opposite side of the guide tracks from the cam. Reduced pressure on the cam side of the guide tracks causes an air stream to pass through the space between the tracks, thereby preventing passage of lubricant in the opposite direction.

The present invention relates to methods of winding yarn, for example, multifilament nylon yarn, onto a package or other storage means at high rates and to apparatus employing high-speed traversing mechanisms for use therein.

Traversing mechanisms suitable for use in winding up yarn at high rates continuously over long periods are becoming increasingly in demand in the synthetic textile industry, especially in the field of nylon yarn manufacture. Such mechanisms are needed for use in association with yarn drawing apparatus where wind up rates as high as 6,000 to 10,000 feet per minute are desired.

Cam and follower mechanisms have been employed in practice, as being most suitable, for effecting reciprocation of the yarn guides and where wind-up rates merely of the order of 2,000 feet per minute have been desired an arrangement comprising a single elongated cam follower which is reciprocated in a lengthwise direction and has many yarn guides fixed to, and outstanding from, one of its sides at suitably spaced points along its length has proved quite satisfactory. However, yarn-guide-traversing mechanisms to be suitable for use in winding-up drawn yarn at rates as high as 6,000 to 10,000 feet per minute must employ a yarn guide and cam follower of much lighter and less bulky overall construction'The yarn guide and follower should have as low a mass as possible consistent with sufficient strength and robustness for them to be able to withstand the rigours of continuous operation over long periods. Furthermore, the cam follower must be as short as possible in order to avoid the occurrence of troublesome flexing during operation. The yarn guide will preferably be in the form of a slotted plate of, say, ceramic material which is caused to reciprocate in its own plane with the yarn passing freely through the slot and in such case there will be no problem offiexing associated with the yarn guide.

There have been a number of suggestions in patent specifications published in recent years of yarn-guidetraversing mechanisms allegdly suitable for use in windingup yarn at high rates and these have all involved the use of a rotary cam having a right-circular cylindrical surface with cam track formed in the surface of the cam of such configuration as to cause, when the cam is rotated about its axis, a follower engaging the cam track to execute a reciprocatory motion transversely of its length and in the direction of extent of the axis of rotation of the cam. The preferred cam track is a groove cut in the cylindrical surface of the cam and the surface of the portion of the follower that runs in the groove is preferably substantially a surface of revolution, for example, a cylindrical surface. Means has been provided, and is necessary, to prevent the follower moving bodily away from the cam out of engagement with the cam track, and means has been provided to ensure that the yarn guide follows a substantially rectilinear path during itsreciprocation and is prevented from rocking, which would, of course, interfere with free passage of yarn through the guide. An example of one such suggested form of traversing mechanisms is to be found described in US. patent specification No. 3,086,722.

It is preferred to use a cam follower formed integrally of a moulded plastics material (such as nylon, or the polyformaldehyde resin marketed under the trade name Del rin by E. I. du Pont de Nemours & Company) and having a yarn guide of suitably wear-resistant material (say a ceramic) secured at its free end by, for example, screw clamping, or, better, encasement of a foot portion of the yarn guide during moulding of the follower. Such plastics materials have a high strength to weight ratio, can satisfactorily withstand severe mechanical shocks, can easily be shaped by moulding, and further have low coefiicients of friction.

Whatever materials be used in the construction of the follower, we have found that, for practical commercial purposes, lubrication is essential in order to reduce wear on parts of the traversing mechanism moving with respect to and in contact with other such parts and, where followers formed of thermoplastic materials are used, to allow of more easy running with attendant lesser heat generation. Heat generation can, of course, be a serious hazard where thermoplastic materials are used for moving parts.

Test runs at high rates of wind-up, for example, 9,000 feet per minute, have revealed that the necessary compactness of the high speed yarn guide traversing mechanisms here under consideration is a hindrance to satisfactory lubrication because lubricant tends to find its way onto the yarn being handled, resulting in a package of dirty smudgy appearance wholly unsuitable for marketing. This contamination of the yarn by the lubricant apparently arises from splashing and mist deposition as well as from seepage along the follower and yarn guide.

The present invention provides a method of winding yarn in which advancing yarn is guided onto a rotating member, say a package, for winding thereon by a reciprocating yarn guide, wherein the yarn guide is continuously reciprocated by means of a compact cam follower that is fixed with respect to the yarn guide, engages a cam track formed at the surface of a right-circular cylindrical rotary cam, and, by means of parallel spaced guide surfaces, is constrained to reciprocate along a substantially rectilinear path transversely of its length and in the direction of extent of the axis of rotation of the cam, the surfaces of the follower that are in sliding contact with surfaces on the rotary cam and also said guide surfaces are lubricated, and a stream of gas is caused continuously to fiow between the guide surfaces and through such clearance as may be between the guide surfaces and the reciprocating follower or yarn guide in such a manner as to prevent lubricant passing in any substantial quantity beyond said guide surfaces towards yarn-engaging portions of the yarn guide whether by seepage, splashing or as a mist.

The invention also provides apparatus for use in winding yarn which comprises means for supplying yarn, say, yarn drawing apparatus, a rotatable member, say a package, on which the yarn can be wound, a yarn guide for guiding the yarn on to the rotatable member whether directly or, better, by way of the surface of a drive roll for the rotatable member, and a yarn-guide-traversing mechanism comprising a compact cam follower that is fixed with respect to the yarn guide and that engages a cam track formed at the surface of a right-circular cylindrical rotary cam, the arrangement being such that, when the cam is rotated about its axis, the follower is caused to execute a reciprocatory motion transversely of its length and in the direction of extent of the axis of rotation of the cam, and parallel spaced guide surfaces for causing the follower to move along a rectilinear path during its reciprocation, means for supplying lubricant to surfaces on the follower that are in sliding contact with other surfaces and to said guide surfaces, and means for causing a stream of gas continuously to flow between the guide surfaces and through such clearance as may be between the guide surfaces and reciprocating surfaces disposed therebetween.

The gas will normally be air and advantageously the air is caused to flow as a stream in aforesaid manner by placing the region on the side of the guide surfaces towards the rotary cam in communication with a source of reduced pressure. Preferably, the rotary cam is mounted within a housing, the yarn guide protrudes through a narrow elongated slot formed in one side of the housing and the interior of the housing is continuously exhausated so as to maintain a continuous and adequate flow of air through the slot. Lubrication of the contacting moving parts of the follower and the rotary cam and of the moving surfaces on the follower or yarn guide contacting said guide surfaces may be effected in any suitable manner and may be effected continuously or intermittently. Thus, for example, the lubricant may be supplied by drip-feed, or as a fine mist or spray.

At high rates of revolution of the cam there may be a tendency for the cam tracks to be starved of lubricant by reason of lubricant being thrown out by centrifugal action. Advantageously, lubricant is led to the base of the cam track through an inclined conduit, say a bore, of suit able dimensions formed in the follower are extending from the upper or the follower surfaces in contact with the guide surfaces to a follower surface in contact with the cam track. Lubricant which is supplied to or accurnulates on that upper surface of the follower then flows under gravity to the cam track.

The continuous flow of gas around the follower also serves to affect some cooling of the follower and this is advantageous where the follower has the form hereinbefore described in which it is formed of a thermoplastic material such as nylon.

A method of winding a yarn in accordance with the invention and apparatus for use therein will now be described by way of example in greater detail with reference to the drawings accompanying the provisional specification (which are not to scale) in which:

FIGURE 1 is a diagrammatic side elevation, partly in section, of apparatus suitable for carrying out the method of the invention;

FIGURE 2 is a diagrammatic plan view on an enlarged scale, and partly in section, of a part of the apparatus as shown in FIGURE 1;

FIGURE 3 is a diagrammatic side view, partly in section, of a part of the apparatus shown in FIGURE 2; and

FIGURE 4 is an end view of the part of the apparatus shown in FIGURE 3, looking from the right-hand end, and rotated 90.

Referring to FIGURE 1 of the drawings, the apparatus includes drawn yarn supply means (not shown) for delivering drawn yarn 1 which is wound, with the aid of a reciprocable yarn guide 2 onto a yarn package 3 arranged to be rotatably driven by a drive roll 4. The yarn 1 is led about a portion of the surface of the drive roll 4 and is printed onto the package 3.

The yarn package 3 is rotatably mounted on the pivotable support 5 which is urged against the surface of the drive roll 4 by the action of tension spring 6 as well as by gravity. The drive roll 4, the package 3, and the support 5 may be of standard construction and they are not described in detail.

The yarn 1 is laid down first on the drive roll 4 because the uncontrolled length of yarn between the yarn guide 2 and the surface of the drive roll 4 can then be made as short as desired and it is in no way influenced by substantial variations in the dimensions of the package 3.

The yarn guide 2 is attached to a yarn-guide traversing mechanism indicated generally by the reference 7. The traversing mechanism 7 includes a positively driven rightcircular cylindrical rotary cam 8 having a cam track (not shown) in the form of a groove of such configuration as to cause a cam follower 9 to execute a reciprocatory motion transversely of its length and in the direction of the extent of the axis of rotation of the cam 8 as the cam 8 rotates. Cam and follower arrangements functioning in this way are, of course, well known and understood and no detailed description of the cam is deemed necessary. Such cams are often termed barrel cams. The axis of rotation of the earn 8 and the axes of rotation of the drive roll 4 and the package 3 are parallel to one another and horizontal.

The cam 8 is mounted within a housing -10, the front side of which is closed by a plate formed of two separable and abutting halves 11a and 11b disposed one above the other that fit snugly together along their edges of contact except over a medial region where they define between them a narrow slot 12 into which the follower 9 protrudes and beyond which the yarn guide 2 attached to the follower 9 extends.

The slot 12, the follower 9, and the yarn guide 2 will now be described in greater detail with reference to FIG- URES 2 to 4 of the drawings.

The follower 9 is indicated generally in FIGURES 2 to 4 by its reference number. The follower 9 is integrally formed by moulding of a plastics material, such as nylon, or the formaldehyde resin marketed under the trade name of Delrin by E. I. du .Pont de Nemours & Company, that has a high strength to weight ratio, high impact strength, and a low coefficient of friction as well as a moderately high softening temperature. The follower 9 has a cam-groove engaging portion 13 at One end that is of uniform circular cross-section and is hollowed-out to reduce its mass and has a yarn-guide-holding portion 14 at its other end that encases the foot of the yarn guide 2. Such encasement is effected during moulding of the follower 9 and proper retention of the yarn guide 2 is ensured by forming the foot of the yarn guide 2 with a nurlnber of holes which become filled with plastics materia The yarn guide 2 is plate-like and is formed at its free end with a yarn-engaging slot 15 and is rounded at that end, as shown in FIGURE 3, to facilitate yarn capture. The yarn guide 2 is preferably formed of a ceramic ma terial.

Next to the yarn-guide-holding portion 14 along the length of the follower 9 is a portion 16 that slidably engages planar and parallel facing guide surfaces 17 and 18 (see FIGURE 2) within the slot 12. The depth of the portion 16, accordingly, is substantially equal to the distance separating the surfaces 17 and 18, and the width of the portion 16 is sufiicient for it easily to be able to withstand forces tending to rotate the follower '9.

Between the slot-engaging portion 16 and the camgroove-engaging portion 13 of the follower 9 is flange portion 19 which, for convenience, is, except where the portion 16 laterally overlaps it, of circular cross-section (see FIGURE 4) and that is of larger diameter than the camgroove-engaging portion 13 of the follower 9 thereby enabling it to act as a spacer member for the follower 9 between the cylindrical surface of the cam 8 and the flat inner surfaces of the plate halves 11a and 11b. The surface of the portion 19 that lies against the surface of the cam '8 is cylindrical to permit flush contact with the cam surface.

As can be seen from FIGURE 2, the depth of the slot 12 varies across its width. The separation between the plate halves 11a and 11b is largest mid-way between the faces of plate halves 11a and 11b. The gap at the mouth of the slot 12 where it overlaps the yarn guide 2 is just sufiicient to provide a small clearance between the slot 12 and the yarn guide 2. By shaping the slot 12 in this way, a channel 20, that serves as a lubricant sump, is formed within the slot 12. Conduits 21 in the form of small bores lead downwardly from the ends of the channel 20 and allow of lubricant drainage. Lubricant is continuously or intermittently supplied to reciprocating surfaces within the slot 12 through a conduit 22, also in the form of a small bore, which extends downwardly through the plate half 11a from supply means (not shown) to a point approximately mid-way along the guide surface 17.

A small downwardly inclined bore 23 formed in the follower 9 extends from the interface between the guide surface 17 and the portion 16 to the hollowed-out interior of the cam-groove-engaging portion 13 and so permits lubricant continuously to flow from that interface to the surfaces of the cam groove.

The interior of the housing is in communication with the surrounding atmosphere only at the slot 12 but is placed in communication with a source of reduced pressure (not shown) through an opening 24 formed in its base. In operation, the interior of the housing 10 is continuously exhausted in order to cause an adequate and continuous flow of air through the slot 12, the effect of which is substantially to effect cooling of follower 9 and to prevent lubricant seeping, splashing or spraying through the slot 12 onto the yarn 1 and the drive roll 4.

The dimensions for the apparatus may suitably be as follows:

Inches Unwound diameter of package 3 6 Distance of axis of package 3 from pivotal axis 9 Diameter of drive roll 4 4 Distance of yarn guide 2 from wind-on point on drive roll 4 Distance by which yarn guide 2 projects beyond front face of plate halves 11a and 11b A; Free length of yarn guide 2 Width of yarn guide 2 4 Diameter of cam 8 6% Stroke of cam 8 6 Number of reciprocations of yarn guide 2 per revolutions of cam 8, 1.

Dimensions of follower 9 inner /2 Diameter of portion 13 outer 1%6 Length of portion 13 Length of portion 14 A Width of portion 14 Depth of portion 14 A Length of portion 16 beyond face of portion 19- Width of portion 16 1% Depth of portion 16 A Diameter of portion 19 Thickness of portion 19 7 to 43 Diameter of bore ,5

In operation the yarnmay be wound at, say, 9,000 feet per minute corresponding approximately to a cam rotational speed of 1,600 rpm.

I claim:

1. In the method of winding yarn by guiding the yarn to a rotating windup member with a reciprocating guide traversing mechanism which includes a barrel cam, a cam follower cooperating therewith, parallel spaced-apart guide rails constraining the follower in a rectilinear path 2. A method as in claim 1 wherein the step of continuously passing the stream of gas is effected by placing the region on the side of the guide rails toward the cam in communication with a source of reduced pressure so as to draw air between the guide rails from the side toward the yarn guide element.

3. A method as in claim 2 including the step of enclosing the cam in a housing and providing a slot for the yarn guide and wherein the reduced pressure is effected by continuously exhausting the housing.

4. A method as in claim 1 wherein the lubricating step is effected by providing an inclined passage in the cam follower extending from one of the surfaces which cooperates with a guide rail to a surface which cooperates with the cam.

'5. Apparatus for winding yarn comprising: means for supplying yarn; a rotatable member for winding up the yarn; a yarn guide for guiding yarn from the supplying means to the rotatable member and a yarn guide traverse mechanism including a n'ghtcircular cylindrical rotary cam having a continuous cam track in its surface, a compact cam follower fixed to said yarn guide and cooperating with said cam track so as to be reciprocated along the path parallel to the axis of said cam, and parallel spaced-apart guide members disposed between said cam and said yarn guide, said guide members having guide surfaces cooperating with said cam follower for restraining the latter to move along a rectilinear path during its reciprocation; means for supplying lubricant to the cooperating surfaces of said follower and said track and to said guide surfaces; and means for preventing passage of lubricant in any substantial quantity between said guide members and toward said yarn guide comprising means for passing a stream of gas between said guide surfaces toward said cam and through any clearance existing between said guide surfaces and said cam follower.

6. Apparatus as in claim 5 wherein said means for supplying yarn is yarn drawing apparatus.

7. Apparatus as in claim 5 including a housing in which said cam is mounted, said housing having a narrow elongated slot through which said yarn guide protrudes, and wherein said means for passing a gas stream includes means for continuously exhausing air from the interior of said housing.

8. Apparatus as in claim 5 wherein said guide members are horizontally disposed one above the other and wherein said lubricating means includes an inclined passage in said cam follower, said passage extending from the cam follower surface which cooperates with the up-- per guide member to a surface which cooperates with said cam track.

References Cited UNITED STATES PATENTS 2,366,963 12/ 1943 Schweiter 24243 X 3,074,286 1/1963 Altice et al. 242-l.5-8.3 1 XR 3,086,722 4/1963 Altice et al. 24243 3,2A8,064 4/1966 Rollings 24243 3,265,315 8/1966 Mueller 24243 X FOREIGN PATENTS 802,430 10/ 8 Great Britain.

STANLEY N. GILREATH, Pnimary Examiner. 

